The unpredictable checkpointing / save system combined with the unskippable cut scenes is really irritating.

I know the solo campaign isn't meant to suffer because of the co-op game, but the way Carver keeps popping back up in the cut-scenes is weird. You've been battling solo through waves of enemies, then you step into a room, a cutscene kicks in and the camera pans back slightly, revealing Carver standing right beside you. And I've just watched a cutscene (a few times: see above) where Carver discusses his backstory, which if you're playing solo, you don't know about or care about. It really feels like the co-op decision was a poor one, it'll get dropped for 4.

On Chapter 17 now, it's really dragging. I've never hated abseiling more than I do now..

Also, bit of an odd casting choice, making TV chef Nigel Slater the main enemy.